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Posted

Yes, that and any others they haven't found yet. Fairly amazing we can see these far away objects at all in my opinion. They're dark objects very far away and usually floating against the backdrop of dark space. I don't think they get too much help in the illumination department from our sun due to the distance.

Posted

Yes, that and any others they haven't found yet. Fairly amazing we can see these far away objects at all in my opinion. They're dark objects very far away and usually floating against the backdrop of dark space. I don't think they get too much help in the illumination department from our sun due to the distance.

 

Yes Deepwater6, we really need to look at things from a different perspective. 

 

At the moment we are having difficulty trying to detect moving things with a background of a massive numbers of stars that don't move but our observation points either orbit around the earth or are at a fixed point on the surface while our planet rotates around our sun and our sun rotates around our galactic centre.

 

I have always said that we should make observations from a point relatively stationary with regards to these 3 different spins and then we will really be able to see what is actually moving as opposed to what we see now.  Unfortunately observations without spin are anathema in the modern world, until some politicians get hit by a space rock that is. ;)

  • 3 months later...
Posted (edited)

https://www.space.com/41679-australia-fireball-photos-videos-august-2018.html

 

Some Australians were lucky to see and catch this one on video.

 

Hello LaurieAG, Its been awhile and I hope you're well. I know you reside in Aussie-land, but I'm not sure which part.. Any chance this was near you, and did you happen to be outside at the right time to catch it?

 

Hi Deepwater6, unfortunately I'm on the opposite side of the country from WA so I missed it. 

 

But that doesn't mean that we don't get them coming overhead around where I live. The following is a link from Youtube video of one in April this year that went from east to west. BTW the black dots in the second video are Flying foxes (or Fruit bats) not birds.

 

Edited by LaurieAG
  • 1 month later...
  • 4 months later...
Posted

Is the ISS module 'ZARYA' coming in at the moment?

 

Satview shows ZARYA and the ISS in the same location but the 'Your position' icon on the map is not the same. Zarya and Tiangong 2 show the same 'Your position' location but the ISS is different, out by half of the circumference.

 

For some strange reason, the norad code for ZARYA is norad 37820U which was the same code used for Tiangong 1.

 

Does anybody else see the different 'Your position' in the maps on the links below?

 

ISS ZARYA http://www.satview.org/?sat_id=37820U

 

ISS http://www.satview.org/?sat_id=25544U

 

TIANGONG II http://www.satview.org/?sat_id=41765U

 

Also, on Friday (February 15, 2019) my local paper had an article about UFO sightings and the image published was almost identical to the photo of Tiangong 1 I took on March 22, 2018, almost 2 weeks prior to its reentry.

  • 3 months later...
Posted

It is Asteroid day on June 30.

 

https://asteroidday.org/

 

Asteroid Day is a global program supporting thousands of independently organized events on June 30th, provides online educational asteroid resources 365 days a year and produces a 24-hour global broadcast with an all-star lineup called Asteroid Day LIVE from Luxembourg.  Your financial support enables us to deliver these programs.

 

Posted

If this is about the headline I am thinking of, it has been estimated that there is a 1 in 7000 chance of hitting Earth, let's see who can use their brain boxes. In a statistical sigma value, how likely is it for it to impact Earth?

 

Keep in mind, there are gravitational effects that we cannot calculate to absolute precision and even the recent intersteller object even followed a path which was not quite within the parameters predicted by general relativity... room for error? Possibly, rule it out, unlikely. We'll only know when it gets close enough.

Posted (edited)

Ok... no one entertaining this?

 

if sigma 5 means there is only a 1 in 3.5 million chance the results are by accident, then chances are less than 1 in a million. A 1 in 10,000 is not very high at all... in terms of sigma values, the asteroid approaching is 1 in 7000. If the norm of sigma 1 is a standard deviation, then sigma 5 is around a 1 in 3.5 million chance that means the 1 in 7000 does leave a large amount of error for the standard deviation. The standard norm of sigma 1 up to 6 will designate the maximum number of defects per million in a process - since 1 in 7000 is less than 1 in a million, this means 1 in 7000 is less than the sigma 1 mark. That means there is plenty room for error. Even a 1 in 10,000 chance of something happening, isn't even enough to be considered statistically significant, nor really is a scientist absolutely sure at a sigma 5 range... sigma 6 is the upper bound that calculates the rationality of something happening in confidence. Mathematically we can say that

 

[math]1\ in\ 7000 << \sigma (5)[/math]

 

and no where near a 1 in a million confidence.

Edited by Dubbelosix
Posted

Let's put this into a rational context with already known calculations in literature.

 

The odds of being struck by lightning in your lifetime is 1 in 80,000 and being killed by a shark is 1 in 3.7 million.

 

Now the odds of 1 of in 7000 is miniscule compared ~ the room for error is a good reason to be worried about the asteroid... and yet scientists are saying in an article just recently that, and I quote, ''All the risk list really means is that the rock has a non-zero chance of striking Earth.''

 

This is just a light way of saying, it is very possible. Even the intersteller object, first ever detected moving through our solar system just before Hawking died, followed an unusual path not predicted using standard general relativity, so that could even mean there is even more room for error. Don't mean to be a doom-sayer, because while there is a chance of hitting us, there is too much room for error to be confident that it won't. But hopefully these odds will be fortunate for us.

  • 4 weeks later...
  • 2 weeks later...
Posted (edited)

WOW, Tiangong II is supposed to re-enter on the 19th. Satview.org has incorrect data if the reentry is this year.

 

BEIJING, July 13 (Xinhua) -- China's Tiangong-2 space lab is planned to be controlled to leave orbit and re-enter the atmosphere on July 19 (Beijing time), China Manned Space Engineering Office (CMSEO) announced on Saturday.

 

http://www.xinhuanet.com/english/2019-07/13/c_138223076.htm

 

http://www.satview.org/?sat_id=41765U

Edited by LaurieAG
Posted

Are we being lucky?  Do these falling satellites always land in "safe sea areas?  Wasn't that way in ancient history.  Anyway, thanks for this. A lot of good information there.

 

This one is actually a controlled landing so you never know your luck.

 

There are also reports that Tiangong II recently went down to an altitude of 240km or so and then returned to it's current altitude reasonably quickly so it will be quite spectacular if it meets the forecast re-entry time.

Posted

This one is actually a controlled landing so you never know your luck.

 

There are also reports that Tiangong II recently went down to an altitude of 240km or so and then returned to it's current altitude reasonably quickly so it will be quite spectacular if it meets the forecast re-entry time.

Can it do that - come down in altitude and then rise back up?  Wouldn't that take pretty fierce winds to give a lift?  Or, could it be that its descent is being helped along with manual aide from Earth?  I seem to remember that one of our ships was guided down - I think into the Pacific where the men were picked up.  Long ago.

Posted

Can it do that - come down in altitude and then rise back up?  Wouldn't that take pretty fierce winds to give a lift?  Or, could it be that its descent is being helped along with manual aide from Earth?  I seem to remember that one of our ships was guided down - I think into the Pacific where the men were picked up.  Long ago.

 

SpaceNews first reported last year that a lowering of the spacecraft’s orbit indicated a probable deorbiting of the spacecraft. 

Tiangong-2 shortly after raised from this lower orbit of 292 by 297 kilometers altitude back to its standard mission orbit and is currently in a 378 by 387 kilometers orbit.

 

https://spacenews.com/china-set-to-carry-out-controlled-deorbiting-of-tiangong-2-space-lab/

 

Satview has it at an altitude of around 280km now but others have reported that it is has already come in today.

http://spaceflight101.com/tiangong-2/category/re-entry/

http://www.satview.org/?sat_id=41765U

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